Adding CopresenceState

components/copresence/copresence_state_impl.cc

+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "base/logging.h"
+#include "base/time/time.h"
+#include "components/copresence/copresence_state_impl.h"
+#include "components/copresence/proto/data.pb.h"
+#include "components/copresence/public/copresence_constants.h"
+#include "components/copresence/public/copresence_observer.h"
+
+namespace copresence {
+
+namespace {
+
+template<class T>
+void CheckUnchangedFields(const T& new_token, const T& current_token) {
+  if (current_token.id.empty())
+    return;
+
+  // These fields identify the token.
+  DCHECK_EQ(new_token.id, current_token.id);
+  DCHECK_EQ(new_token.medium, current_token.medium);
+
+  // start_time may not be changed.
+  DCHECK_EQ(new_token.start_time, current_token.start_time);
+}
+
+void UpdateToken(const TransmittedToken& new_token,
+                 TransmittedToken* current_token) {
+  CheckUnchangedFields(new_token, *current_token);
+
+  current_token->stop_time = new_token.stop_time;
+  current_token->broadcast_confirmed = new_token.broadcast_confirmed;
+}
+
+void UpdateToken(const ReceivedToken& new_token,
+                 ReceivedToken* current_token) {
+  CheckUnchangedFields(new_token, *current_token);
+
+  current_token->last_time = new_token.last_time;
+  if (new_token.valid != ReceivedToken::UNKNOWN)
+    current_token->valid = new_token.valid;
+}
+
+}  // namespace
+
+
+// Public functions.
+
+CopresenceStateImpl::CopresenceStateImpl() {}
+
+CopresenceStateImpl::~CopresenceStateImpl() {}
+
+void CopresenceStateImpl::AddObserver(CopresenceObserver* observer) {
+  DCHECK(observer);
+  bool not_duplicate = observers_.insert(observer).second;
+  DCHECK(not_duplicate);
+}
+
+void CopresenceStateImpl::RemoveObserver(CopresenceObserver* observer) {
+  DCHECK(observer);
+  int elts_deleted = observers_.erase(observer);
+  DCHECK_GT(elts_deleted, 0);
+}
+
+const std::vector<Directive>& CopresenceStateImpl::active_directives() {
+  return active_directives_;
+}
+
+const std::map<std::string, TransmittedToken>&
+CopresenceStateImpl::transmitted_tokens() {
+  return transmitted_tokens_;
+}
+
+const std::map<std::string, ReceivedToken>&
+CopresenceStateImpl::received_tokens() {
+  return received_tokens_;
+}
+
+// TODO(ckehoe): Only send updates if the directives have really changed.
+void CopresenceStateImpl::UpdateDirectives(
+    const std::vector<Directive>& directives) {
+  active_directives_ = directives;
+  UpdateTransmittingTokens();
+
+  for (CopresenceObserver* observer : observers_)
+    observer->DirectivesUpdated();
+}
+
+void CopresenceStateImpl::UpdateTransmittedToken(
+    const TransmittedToken& token) {
+  UpdateToken(token, &transmitted_tokens_[token.id]);

[xiyuan, 2014/12/18 18:10:51]

General question: when would a token be removed from |transmitted_tokens_| and
|received_tokens_|? It seems tokens are only added. Would this be a problem?

[Charlie, 2014/12/19 03:53:33]

Currently this doesn't happen. This is useful to a point, since past tokens are
still useful info. Added a TODO to limit the number that accumulate.

+  for (CopresenceObserver* observer : observers_)
+    observer->TokenTransmitted(transmitted_tokens_[token.id]);
+}
+
+// TODO(ckehoe): Check which tokens are no longer heard and report them lost.
+void CopresenceStateImpl::UpdateReceivedToken(const ReceivedToken& token) {
+  DCHECK(!token.id.empty());
+
+  // TODO(ckehoe): Have CopresenceManagerImpl::AudioCheck() use this to check
+  // if we can hear our token, and delete the logic from the AudioManager.
+  if (transmitted_tokens_.count(token.id) > 0) {
+    transmitted_tokens_[token.id].broadcast_confirmed = true;
+    for (CopresenceObserver* observer : observers_)
+      observer->TokenTransmitted(transmitted_tokens_[token.id]);
+  } else {
+    ReceivedToken& stored_token = received_tokens_[token.id];
+    UpdateToken(token, &stored_token);
+
+    // The decoder doesn't track when this token was heard before,
+    // so it should just fill in the last_time.
+    // If we've never seen this token, we populate the start time too.
+    if (stored_token.start_time.is_null())
+      stored_token.start_time = token.last_time;
+
+    for (CopresenceObserver* observer : observers_)
+      observer->TokenReceived(stored_token);
+  }
+}
+
+void CopresenceStateImpl::UpdateTokenStatus(const std::string& token_id,
+                                            TokenStatus status) {
+  if (transmitted_tokens_.count(token_id) > 0) {
+    LOG_IF(ERROR, status != VALID)
+        << "Broadcast token " << token_id << " is invalid";
+  } else if (received_tokens_.count(token_id) > 0) {
+    received_tokens_[token_id].valid = status == VALID ?
+        ReceivedToken::VALID : ReceivedToken::INVALID;
+    for (CopresenceObserver* observer : observers_)
+      observer->TokenReceived(received_tokens_[token_id]);
+  } else {
+    LOG(ERROR) << "Got status update for unrecognized token " << token_id;
+  }
+}
+
+
+// Private functions.
+
+void CopresenceStateImpl::UpdateTransmittingTokens() {
+  std::set<std::string> tokens_to_update;
+  for (const auto& token_entry : transmitted_tokens_)
+    tokens_to_update.insert(token_entry.first);
+
+  for (const Directive& directive : active_directives_) {
+    const TokenInstruction& instruction = directive.token_instruction();
+    if (instruction.token_instruction_type() == TRANSMIT) {
+      tokens_to_update.erase(instruction.token_id());
+
+      TransmittedToken& token = transmitted_tokens_[instruction.token_id()];
+      token.id = instruction.token_id();
+      token.medium = instruction.medium();
+      token.start_time = base::Time::Now();
+      token.stop_time = base::Time::Now() +
+          base::TimeDelta::FromMilliseconds(directive.ttl_millis());
+
+      for (CopresenceObserver* observer : observers_)
+        observer->TokenTransmitted(token);
+    }
+  }
+
+  // Tokens not updated above are no longer transmitting.
+  base::Time now = base::Time::Now();
+  for (const std::string& token : tokens_to_update) {
+    if (transmitted_tokens_[token].stop_time > now)
+      transmitted_tokens_[token].stop_time = now;
+    for (CopresenceObserver* observer : observers_)
+      observer->TokenTransmitted(transmitted_tokens_[token]);
+  }
+}
+
+}  // namespace copresence